During adolescence, youth undergo pivotal biological, emotional, and cognitive shifts. Concomitant with immense internal shifts, adolescent peer relations become increasingly complex (e.g., cliques) and challenging (e.g., peer pressure) and, as teens struggle to define their young adult role, relationships within the family can become increasingly strained and conflictual. When youth experience difficulties navigating the transitions of adolescence, they are at heightened risk for developing a variety of mental health disorders (e.g., depression, anxiety), maladaptive behavior patterns (e.g., self-destructive or risk-taking behaviors) and academic failure. Parents are often at a loss for how to communicate with their teen to help them through the turmoil of adolescence. The resulting elevated levels of parental stress not only negatively impacts adolescent adjustment, but also places parents at heightened risk for their own mental health problems, particularly depression. This Phase II SBIR project will continue the research and development (R&D) of a unique parent training intervention product, the Parent Guide to Adolescent Social-Behavioral Development (PGA). PGA is specifically designed to help parents learn and practice strategies to effectively help their teen through the interpersonal struggles of adolescence (with peers and family members). PGA will help parents learn how to work collaboratively with their adolescent to achieve social goals, thereby building parental confidence, reducing related parental stress, and enhancing parent-teen communication. The full PGA product will offer manualized, structured scripts for 12 parent group sessions, a wide array of written, video, and web-based intervention materials for parents, and a variety of online professional development and implementation support resources for providers. Once the program is finalized, a scientific evaluation of its efficacy will be conducted. Parents will be randomly assigned to PGA treatment (TX) or attention control (AC) conditions (n=72 each). Efficacy will be evaluated by examining changes in (a) parent understanding of social issues facing adolescents and social problem solving skills; (b) parental self-efficacy for helping their teen; (c) parenting stress; (d) adolescent social and behavioral functioning; and (e) quality of the parent-teen relationship (e.g., communication, conflict) as a function of treatment condition. We expect the TX condition to show significant positive change in each outcome area versus the AC condition which is expected to show little to no change. PGA will be a highly unique, innovative product that will fill a niche in the intervention marketplace not currently filled through any other commercialized product. This SBIR will yield a valuable resource for providers and parents with the potential to make a significant impact on the lives of adolescents and their families.